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CNN's What is black carbon? The latest way humans are causing changes in Antarctica doesn't actually say anything about what black carbon is. Neither does The Guardian's Black carbon pollution from tourism and research increasing Antarctic snowmelt, study says.

I assume these are particulates due to incomplete burning of hydrocarbon fuels, and those that reach Antarctica must have a fairly small size in order to get there.

The ones that absorb light most effectively and melt snow may also have some constrains on composition, though maybe "mostly carbon" is all that can be said.

Has there been an attempt to identify the size and composition of black carbon particles that are the primary contributors to snowmelt in Antarctica?

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    $\begingroup$ It seems that you're aware that incomplete combustion of hydrocarbons produces carbon particles, and that those particles are black. Given that, I'm curious about what makes you suspect that "black carbon" is anything more specific than that? $\endgroup$ Feb 28 at 17:13
  • $\begingroup$ What there is, is by no means "exact", that's the point. Anything being mostly carbon, with small dimension. $\endgroup$
    – Mithoron
    Feb 28 at 17:50
  • $\begingroup$ @IlmariKaronen science can and does analyze the heck out of anything. There's density, size, shape, aromaticity, complex index of refraction, reactivity, other chemical constituents, isotopic anomalies to name a few. $\endgroup$
    – uhoh
    Feb 28 at 22:29
  • $\begingroup$ @uhoh: I'm sure it has been analyzed, probably in enough detail to fill several scientific journal articles, if not entire books. But if that's what you want to know, I'd suggest rewriting the title and beginning of your question, because right now it reads as if you're asking for a definition ("what is black carbon?"), not for an analysis of its physical and chemical properties. Maybe lead with something like your last paragraph (e.g. "what is the size distribution and chemical composition of black carbon particles found on snow in Antarctica?") if that's what you actually want to know. $\endgroup$ Feb 28 at 23:02
  • $\begingroup$ @IlmariKaronen that's exactly why in Stack Exchange we have question posts and not just titles. This isn't Quora. And we answer the full question post, not answer the title. $\endgroup$
    – uhoh
    Feb 28 at 23:11

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This issue has been extensively studied and identified. A Google search regarding the particle size of black carbon will yield a plethora of information.

Chemically, black carbon (BC) is a component of fine particulate matter (PM ≤ 2.5 µm in aerodynamic diameter).

See this link for a paper by Matsui and co-authors which may answer some aspects regarding your question about identifying the size and composition of black carbon particles, and their radiative effects.

Quite obviously, the sources of black carbon are from anything emitting black smoke. Principal examples are coal-fired power plants, oil field flares and oil refineries, diesel exhaust, and in particular overseas commercial transport shipping, namely, container ships.

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    $\begingroup$ an other way to say this is,airborne soot from incomplete combustion of hydrocarbons. $\endgroup$ Feb 28 at 5:04
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    $\begingroup$ Welcome to Stack Exchange! This is a great start but we'd call this a link-only answer; if the link breaks there's no answer here to back it up. "Chemically, black carbon (BC) is a component of fine particulate matter (PM ≤ 2.5 µm in aerodynamic diameter)" does not say anything more about the chemical or physical nature of black carbon than the name "black carbon" already tells us. You also haven't addressed the range of sizes necessary for transport all the way to Antarctica. "Google it" and "go read this paper" are helpful comments but by themselves are not Stack Exchange answers. $\endgroup$
    – uhoh
    Feb 28 at 12:06
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    $\begingroup$ @uhoh I think you can not really find an answer to this question more than this answer. Simply because the specification of black carbon does not actually one thing or a "primary component". What falls on the ground is even different than what's in the air, as prior to falling it clumps together and might react further removing radicals. $\endgroup$
    – paul23
    Feb 28 at 15:28
  • $\begingroup$ @paul23 so "... in the context of snow-melting particulates reaching Antarctica" narrows it down somewhat, right? See also this comment. The more that's understood about the nature of the particles that are causing snow to melt in Antarctica, the better one can address which sources of black carbon particulates may be contributing to snow melting, and go beyond "burning is bad". $\endgroup$
    – uhoh
    Feb 28 at 22:30
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Black carbon, aka "soot", is, in the context of Antarctica, the product of the ocean transport industry that brings tourists and supplies to Antarctica.

Ocean transport is poorly regulated and commonly allows the burning of both low grade fuels and "bunk" oil at open sea (which is a notoriously filthy emitter of soot). Although cruise ships are unlikely to burn bunk oil, it is possible that resupply ships burn bunk oil in travelling to Antarctica.

Soot particles don't travel particularly long distances, eliminating other sources such as forest tires, truck transport, and industry, in the case of Antarctica. However, as soot travels, the particles may coalesce into much larger particles that both warm the surrounding air with absorbed solar radiation, and warm surrounding snow and ice when settled out of the atmosphere.

Because soot is insoluble, it remains on a surface until it is washed away. This is made difficult because soot melts through transparent ice where it continues to absorb solar radiation, causing melting, but out of reach of surface rinsing. Over time the warming effects of deposited soot multiply as soot layers become more concentrated by this preferential melting process.

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